全文获取类型
收费全文 | 3945篇 |
免费 | 180篇 |
国内免费 | 7篇 |
专业分类
耳鼻咽喉 | 67篇 |
儿科学 | 56篇 |
妇产科学 | 64篇 |
基础医学 | 630篇 |
口腔科学 | 520篇 |
临床医学 | 224篇 |
内科学 | 676篇 |
皮肤病学 | 109篇 |
神经病学 | 381篇 |
特种医学 | 106篇 |
外科学 | 467篇 |
综合类 | 7篇 |
预防医学 | 296篇 |
眼科学 | 82篇 |
药学 | 261篇 |
中国医学 | 29篇 |
肿瘤学 | 157篇 |
出版年
2023年 | 38篇 |
2022年 | 32篇 |
2021年 | 64篇 |
2020年 | 55篇 |
2019年 | 89篇 |
2018年 | 135篇 |
2017年 | 102篇 |
2016年 | 111篇 |
2015年 | 134篇 |
2014年 | 147篇 |
2013年 | 177篇 |
2012年 | 301篇 |
2011年 | 376篇 |
2010年 | 181篇 |
2009年 | 123篇 |
2008年 | 250篇 |
2007年 | 280篇 |
2006年 | 264篇 |
2005年 | 209篇 |
2004年 | 176篇 |
2003年 | 146篇 |
2002年 | 137篇 |
2001年 | 58篇 |
2000年 | 50篇 |
1999年 | 47篇 |
1998年 | 13篇 |
1997年 | 12篇 |
1996年 | 7篇 |
1995年 | 10篇 |
1994年 | 10篇 |
1993年 | 10篇 |
1992年 | 26篇 |
1991年 | 30篇 |
1990年 | 28篇 |
1989年 | 19篇 |
1988年 | 23篇 |
1987年 | 12篇 |
1986年 | 15篇 |
1985年 | 20篇 |
1984年 | 13篇 |
1983年 | 9篇 |
1978年 | 8篇 |
1975年 | 7篇 |
1974年 | 9篇 |
1973年 | 6篇 |
1972年 | 9篇 |
1971年 | 7篇 |
1968年 | 11篇 |
1967年 | 9篇 |
1966年 | 13篇 |
排序方式: 共有4132条查询结果,搜索用时 15 毫秒
1.
Monitoring left ventricular dilation in mice with PET. 总被引:3,自引:0,他引:3
Lars Stegger Klaus P Sch?fers Ulrich Fl?gel Lefteris Livieratos Sven Hermann Christoph Jacoby Petra Keul Edward M Conway Otmar Schober Jürgen Schrader Bodo Levkau Michael Sch?fers 《Journal of nuclear medicine》2005,46(9):1516-1521
Molecular imaging by small-animal PET is an important noninvasive means to phenotype transgenic mouse models in vivo. When investigating pathologies of the left ventricular (LV) myocardium, the serial assessment of LV volumes is important. By this, the presence of LV dilation as a sign of developing heart failure can be detected. Whereas PET is usually used to derive biochemical and molecular information, functional parameters such as ventricular volumes are generally measured using echocardiography or MRI. In this study, a novel method to monitor LV dilation in mice with PET is presented and evaluated using cardiac MRI. METHODS: A semiautomatic 3-dimensional algorithm was used to delineate the LV myocardial wall on static PET images depicting myocardial glucose metabolism ((18)F-FDG PET) for 20 mice: 10 wild-type and 10 genetically modified littermates designed to develop a dilative cardiomyopathy phenotype (cardiomyocyte-specific knockout of survivin). The volume enclosed by the 3-dimensional midmyocardial contour was calculated as a measure for LV volume for each mouse. Data were compared with ventricular volumes measured by MRI in the same animals. RESULTS: LV volumes obtained by PET and MRI correlated well (R = 0.89) for hearts with small and large left ventricles. In accordance with the hypothesis, the LV volumes were increased significantly for transgenic mice examined at an older age compared with those examined at a younger age (MRI: 160.5 +/- 25.7 microL vs. 114.7 +/- 15.2 microL [P = 0.012]; PET: 129.3 +/- 15.3 microL vs. 73.8 +/- 15.0 microL [P < 0.001], all values shown as mean +/- SD; for MRI, mean of end-diastolic and end-systolic volumes are given), whereas they did not for their wild-type littermates (MRI: 106.2 +/- 12.3 microL vs. 94.7 +/- 14.6 microL [P = 0.214]; PET: 82.6 +/- 20.9 microL vs. 65.0 +/- 16.9 microL [P = 0.185]). CONCLUSION: Evaluation and quantitation of LV dilation in both control and cardiomyopathic mice can be reliably and serially performed using small-animal PET and (18)F-FDG, yielding useful functional information in addition to metabolic data. 相似文献
2.
Aldo Cunha Medeiros Irami Araújo Filho Vítor Brasil Medeiros Laíza Araújo Mohana Pinheiro Flávio Henrique Miranda Araújo Freire Italo Medeiros Azevedo José Brand?o-Neto 《Journal of investigative surgery》2007,20(1):41-48
After total gastrectomy, the ileocecal graft may act as a reservoir and protect against reflux but give rise to transposition of the ileum and cause possible changes in bile acid metabolism and nutrition. This study compared the ileocecal graft and jejunal pouch. Male Wistar rats weighing 265 +/- 22 g were submitted to sham operation (S), ileocecal interposition graft (IIG), and jejunal pouch interposition graft (JP) after total gastrectomy. Eight weeks later, the esophagus was examined for evidence of esophagitis. Nutritional biochemistry and weight profile were documented preoperatively and 8 weeks after surgery. The oral glucose tolerance test was performed. Thirty-three rats were operated on and 30 survived for 8 weeks. Esophagitis occurred in seven JP rats. Body weight was significantly higher in IIG than in JP rats (p < .05). Normal glucose tolerance to intragastric glucose load was observed in sham and operated rats. JP rats had a significant decrease in serum albumin, glucose, transferrin, hemoglobin, iron, folate, and calcium, compared to sham (p < .05). Cobalamine was significantly lower in IIG rats than in JP rats (p < .05). In the IIG and JP groups, serum/hepatic total bile acid did not differ significantly from preoperative and sham values. In conclusion, the IIG interposition graft in rats prevented esophagitis, preserved nutrition, and did not interfere with enterohepatic total bile acid circulation. 相似文献
3.
Aureo L DePaula Antonio L V Macedo Claudio R Cernea Vladimir Schraibman Jacques Pinus José R Milanez José E Succi Flávio C Hojaij Dorival de Carlucci Sunao Nishio 《Otolaryngology--head and neck surgery》2006,135(5):710-713
BACKGROUND: Gastric pull-up is a useful method for reconstruction of the upper digestive tract, with considerable morbidity/mortality, especially in esophageal cancers (EC). OBJECTIVE: To analyze the experience of a multidisciplinary team with a laparoscopic gastric pull-up (LGPU) method, with or without thoracoscopy, in a series of 120 patients with EC. STUDY DESIGN: Retrospective. PATIENTS AND METHODS: From 1992 to 2004, 120 EC [cervical/cervicothoracic (3.0%), middle third (15.0%), and inferior third (82.0%)]. Most were squamous cell carcinomas (47.0%) and adenocarcinomas (34.0%). Stomach was dissected and mobilized exclusively by laparoscopy. Occasionally, laparoscopic approach was extended cranially, until connecting with cervical dissection. In other cases, dissection of thoracic esophagus was accomplished through a thoracoscopic approach. RESULTS: Eighty-one patients (68.0%) had LGPU; 39 (32.0%) needed thoracoscopy. Mortality was 5.9%. Complications were fistula (10.0%) and pneumonia (10.0%). All fistulae closed spontaneously; 89.2% of patients could swallow a normal oral diet. CONCLUSION: Low morbidity/mortality of LGPU for EC compared favorably with conventional techniques. 相似文献
4.
5.
G Pialoux F Mouly J F Cadranel J F Fléjou P Marcellin J Belghiti 《Gastroentérologie clinique et biologique》1992,16(8-9):705-707
In progressive systemic scleroderma, a disease of protean manifestations, involvement of the gastrointestinal tract is noted infrequently in patients who are asymptomatic, and is rarely fatal. We report the case of a 65-year-old woman who was admitted for ascitis related to a non A, non B cirrhosis. The patient presented with bacterial peritonitis due to colonic perforation by fecal impaction associated with sclerodermic involvement. Pathologic study of the resected colon showed that the true muscularis was very atrophic and fibrotic, characteristic of scleroderma. To our knowledge, this cause of ascitic fluid infection has not been previously reported. 相似文献
6.
7.
Jan Lycke Bo Svennerholm Anders Svenningsson Walter Muranyi Rolf M. Flügel Oluf Andersen 《Journal of neurology》1994,241(4):204-209
The role of human spumaretrovirus (HSRV) infections in the pathogenesis of multiple sclerosis (MS) was investigated with recombinant HSRV env-specific enzyme-linked immunosorbent assay. The presence of HSRV antibodies was determined in pairs of serum and cerebrospinal fluid (CSF) samples from 60 MS patients. In 7 of these patients serial serum and CSF samples were obtained in relation to the clinical activity of the disease during a period of 2 years. No increased antibody reactivity was demonstrable in the MS population compared with 14 aseptic meningitis patients, 50 blood donors and 16 healthy controls. Slightly elevated levels of antibodies were demonstrable in serum and/or CSF in 4 MS patients but also in 1 patient with aseptic meningitis, 1 blood donor and 1 child. No marked serum or CSF HSRV antibody fluctuation was observed in the MS patients followed longitudinally. Thus, this study does not support the involvement of HSRV in the pathogenesis of MS. 相似文献
8.
The authors present a case of tuberous sclerosis with marked pulmonary involvement, confirmed by both radiological and pathological studies. The radiological manifestations and basic pathology of this rare condition are reviewed with emphasis on differential diagnosis. 相似文献
9.
Camila Oliveira Rodini Flávia Sirotheau Corrêa Pontes Hélder Ant?nio Rebelo Pontes Paulo Sérgio da Silva Santos Marina Gallottini Magalh?es Décio Santos Pinto 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2007,104(4):e50-e55
Leiomyosarcoma of the oral cavity is a very rare tumor associated with aggressive clinical behavior and low survival. In this paper, we report 2 cases of leiomyosarcoma, affecting the gingival mucosa of a 54-year-old female and the maxillary bone of a 63-year-old male. Histologically, the tumors were composed of variably oriented fascicles of spindle-shaped cells with cigar-shaped nuclei and eosinophilic cytoplasm. The lesions were treated by surgical resection. Immunoreactivity to anti-vimentin, anti-smooth muscle actin, anti-desmin, anti-laminin, and anti-muscle-specific actin antibodies were found; conversely, the tumor cells were negative for anti-S100 and AE1/AE3 proteins. This report emphasizes the role of immunohistochemical study for correct diagnosis of leiomyosarcoma. 相似文献
10.
The diagnosis of community acquired pneumonia (CAP) is based on a patient history with respiratory symptoms and additional symptoms and signs such as fever over more than 4 days, dyspnea and tachypnea and/or a positive lung auscultation. Despite recently developed tests, radiology is a key diagnostic procedure for confirming CAP. Importantly, the first treating physician must judge whether to hospitalize a patient or not. Two major scoring systems allow judgement of severity and short-term prognosis. In general, in patients with mild or moderate pneumonia who can be treated on an ambulatory basis, no specific microbiological diagnosis must be performed. If, for clinical or epidemiological reasons a gram stain is done, it must be obtained from purulent sputum. Recent tests may help in discriminating between viral and bacterial pneumonia (procalcitonin test) or determine the bacteria responsible for acute disease (pneumococcal antigen test using urine). 相似文献